Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
4
|
| pubmed:dateCreated |
1990-11-19
|
| pubmed:abstractText |
Blood pressure and pulse interval are characterized not only by erratic variations but also by rhythmic fluctuations at low-, mid-, and high-frequency (0.025-0.07, 0.07-0.14, and 0.14-0.35 Hz, respectively). However, information on these phenomena has largely been derived from analysis of short-term recordings taken in standardized laboratory conditions. In seven normotensive and 10 untreated mild essential hypertensive subjects, power spectrum analysis was performed on the intra-arterial blood pressure and pulse interval signal collected over a 24-hour period using the fast Fourier transform algorithm and splitting the recording into contiguous segments of 256 beats. About 70% of the segments were suitable for the analysis; the segments excluded for a nonstationary signal amounted to only 30%. All powers were characterized by a high segment-to-segment variability, but in each subject the mid- and high-frequency powers of diastolic blood pressure and the mid-frequency power of systolic blood pressure were markedly reduced during the night as compared with the daytime period, whereas the opposite occurred for the low- and high-frequency powers of the pulse interval. Over the 24-hour period, mid- and high-frequency powers of blood pressure were positively correlated to each other, but both accounted for less than 25% of the 24-hour blood pressure variance. No difference between mean normalized power values of normotensive and hypertensive subjects was observed.(ABSTRACT TRUNCATED AT 250 WORDS)
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Oct
|
| pubmed:issn |
0194-911X
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
16
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
414-21
|
| pubmed:dateRevised |
2004-11-17
|
| pubmed:meshHeading | |
| pubmed:year |
1990
|
| pubmed:articleTitle |
Sequential spectral analysis of 24-hour blood pressure and pulse interval in humans.
|
| pubmed:affiliation |
Cattedra di Semeiotica Medica, Università di Milano, Italy.
|
| pubmed:publicationType |
Journal Article
|